Device for identifying a person or an object

ABSTRACT

The invention provides a device ( 10 ) for identifying a person or an object. The device ( 10 ) includes a transparent body ( 42 ), and embedded within the transparent body ( 42 ), a printed circuit board (PCB) ( 46 ), a plurality of light emitting diodes (LEDs) ( 48 ) electrically connected to the PCB ( 46 ), and a diffuser ( 16 ). The diffuser ( 16 ) is arranged to diffuse light emitted from the LEDs ( 48 ) thereby to illuminate the transparent body ( 42 ) to form a light source for identifying a person or an object attached to the device ( 10 ).

BACKGROUND OF THE INVENTION

THIS invention relates to a device for identifying a person or anobject, and more specifically to a device which utilises light toidentify a person or an object in dark or dim conditions.

Chemical light sticks for identifying a person in certain circumstances,for example under water, are known. Conventional chemical light sticksgenerally include a first chemical in an outer, flexible tube and asecond chemical sealed within an inner glass tube inside the outer,flexible tube. To activate the light stick the outer tube is bent untilthe inner tube breaks and releases the first chemical into the secondchemical to produce a fluorescent glow. The known types of chemicallight sticks are available in different sizes and are marketed underdifferent names, for example GLO-STICK, CYLUME, LIGHT-STICK, CHEM-STICKand CHEM-LIGHT.

A problem associated with known light sticks of the type described aboveis that the chemicals sustain the fluorescent glow for a limited timeonly, generally in the region of six hours, and consequently, undernormal circumstances, these sticks cannot be re-used. Also, theactivation of these light sticks is dependent upon the proper contactingof two chemicals, and consequently these sticks have to be used beforean expiry date and often are defective upon purchase.

It is an object of the present invention to provide an alternativelight-emitting device for identifying a person or an object which isrelatively long-lasting, re-usable and robust.

SUMMARY OF THE INVENTION

According to the invention there is provided a device for identifying aperson or an object comprising:

-   -   a transparent or translucent body, and    -   embedded within the transparent or translucent body,        -   a printed circuit board (PCB),        -   a plurality of light emitting diodes (LEDs) electrically            connected to the PCB, and        -   a diffuser for diffusing light emitted from the LEDs thereby            to illuminate the transparent or translucent body to form a            light source for identifying a person or an object attached            to the device.

In a preferred embodiment of the invention, the diffuser includes atapered portion defining a surface which is inclined relative to alongitudinal axis of the device at an angle of between 25° and 45°,preferably at an angle of approximately 30°.

In a particularly preferred arrangement, the device includes a housingdefining a chamber for at least one battery. In this embodiment, thediffuser may form at least part of the battery housing.

Typically, the PCB is connected to the battery housing and is arrangedto hold between three and six LEDs within the transparent or translucentbody.

The LEDs and the diffuser preferably are arranged so that, when thetransparent or translucent body is illuminated, the light source isvisible from all sides of the device.

The device may include attachment means for attaching it to a person oran object.

The device may also include a switch for controlling the flow of currentthrough the LEDs.

The switch may comprise a rotatable member which is threadably engagedwith an end cap so as to be displaceable relative to the end cap betweenan operative position in which it contacts a terminal on a batterywithin the battery chamber and an inoperative position in which it isspaced from the terminal of the battery.

Alternatively, the switch may be arranged to operate under pneumatic orhydraulic pressure.

Typically, elastomeric O-rings form watertight seals on the end cap andon the rotatable switch member.

The device may also include a second PCB within the battery chamber forconnecting a battery contact spring to a wire extending from the firstPCB.

Conveniently, the transparent or translucent body is moulded from anepoxy resin, possibly with colour tints, and the PCB defines a pluralityof openings for allowing the resin through the PCB during the mouldingof the body.

In one arrangement, the battery housing is formed from aluminium,typically a marine grade aluminium, and includes a detachable, aluminiumend cap.

In a configuration which produces a preferred strength and quality oflight, the transparent or translucent body includes a 19 mm diametercylindrical section, and six LEDs of 6 mm diameter are embedded withinthe cylindrical section, adjacent the diffuser, in a circularconfiguration.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail, by way of exampleonly, with reference to the accompanying drawings in which:

FIG. 1 shows a perspective view of an identifier according to thepresent invention;

FIG. 2 shows a cross-sectional view of the identifier illustrated inFIG. 1; and

FIG. 3 shows a side view of the identifier according to the invention.

DESCRIPTION OF AN EMBODIMENT

FIG. 1 of the drawings illustrates an identifier 10 according to thepresent invention. As can be seen, the identifier includes a batteryhousing 12 which has a cylindrical portion 14, a tapered portion 16 anda connecting stem 18. In this embodiment of the invention, the batteryhousing is formed from aluminium, typically a marine grade aluminium,and is seen in FIG. 2 to define a chamber 20 for a battery 22 in theform of a single 12V super alkaline cell.

A knurled end cap 24 carrying a thread 26 is engageable with acorresponding thread 28 on the cylindrical portion 14 of the batteryhousing so as to be detachable for battery replacement. The end cap 24carries an elastomeric O-ring 30 in an annular groove 32 which forms awatertight seal with the cylindrical portion 14 of the housing 12, inuse. A partly threaded bore 34 in the end cap 24 is sized to receive apartly threaded, rotatable switch member 36 which holds an elastomericO-ring 38 for forming a watertight seal between the rotatable switchmember and the end cap. Both O-rings 30 and 38 are silicone-based, highpressure rated O-rings.

In the illustrated embodiment, rotation of the switch member 36 relativeto the end cap 24 displaces the member between an inoperative position(as illustrated in FIG. 2) in which it is withdrawn from the battery 22and an operative position (not illustrated) in which it contacts thenegative terminal of the battery. The end cap 24 also includes anaperture 40 for receiving a ring or the like (not shown) for attachingthe identifier to a person or an object.

The battery housing 12 is embedded in a transparent body 42 which isformed in a cold moulding process from an epoxy resin, typically NH64FRwhich is available from Elite Chemical Industries (Pty) Ltd. In thisembodiment of the invention, the resin includes a colour tint forfacilitating a red glow within the body 42.

A rivet 44 connects a printed circuit board (PCB) 46 to the stem 18 ofthe battery housing so as to position six high-intensity or ultrahigh-intensity, red light emitting diodes (LEDs) 48 around the stem, asillustrated. The PCB 46 holds the LEDs 48 in desirable locations withinthe transparent body 42 and controls the flow of current to these LEDs.An important feature of the PCB 46 is that it includes six openings (notillustrated) along the periphery thereof for allowing the epoxy resin toflow through the PCB in one direction and for air to escape past the PCBin the opposite direction during moulding.

The PCB 46 is electrically connected to a second PCB 50 inside thebattery chamber 20 via a wire 52, and a plastics insulator 54 above thePCB 50 allows for charge separation. The PCB 50 provides a link betweenthe wire 52 and a battery contact spring 56 and insulates the positiveterminal of the battery 22 from the negatively charged battery housing12.

In the illustrated embodiment, the tapered portion 16 of the batteryhousing 12 acts as a diffuser for diffusing light emitted from the LEDs,thereby to illuminate the transparent body 42 to form a light source foridentifying a person or object attached to the device.

In one application, the identifier 10 may be used to identify ascuba-diver under water. In this application, once the battery 22 hasbeen loaded into the battery chamber 20 and the end cap 24 has beensecurely connected to the battery chamber, the switch member 36 isrotated into contact with the battery so as to close a circuit betweenthe positive and negative terminals of the battery. With the circuitclosed, current flows through the end cap 24, the battery housing 12,the rivet 44, the PCB 46 and the LEDs 48, and then back to the battery22 via the wire 52, the PCB 50 and the contact spring 56. As light isemitted from the LEDs into the transparent body 42, the light isdiffused by the diffuser 16, and is deflected, reflected and refractedin the manner illustrated in FIG. 3 to produce a red glow within thebody 42. It should be appreciated that the glow in the body 42 isvisible from all sides of the identifier 10. The identifier is thenconnected to the diver's clothing or equipment by means of a connectingring extending through the aperture 40 in the switch member 36 toidentify the diver under water.

It will be appreciated that although the identifier has been describedabove with reference to a rotatable switch, the switch could be arrangedto operate under pneumatic or hydraulic pressure. For example, theidentifier may be connectable to a high/low pressure stage in a scubasystem so that the switch activates upon the opening of the cylindervalve and is deactivated when the cylinder valve is sealed anddepressurised.

It will also be appreciated that although the invention has beendescribed above with reference to red LEDs, various other coloured LEDs,for example amber, blue or green, could be used. Furthermore, the LEDscould be arranged to emit white light or, for military applications,infra-red light, if desired. In other, non-illustrated embodiments ofthe invention, the LEDs are arranged to emit dual tones and/or to flashon and off.

Furthermore, it will be appreciated that apart from scuba-divingapplications, the identifier 10 could be used in many otherapplications, for example as an identifier for people or objects inmining applications, military applications, emergency servicesapplications, or recreational applications including fishing, cycling ormountain climbing after sunset or before sunrise.

In another, non-illustrated embodiment of the invention, the identifier10 includes a rechargeable battery unit instead of the battery 22.

A major advantage of the identifier according to the embodiment of theinvention described above is that it is long-lasting and hence can bere-used a number of times. It is anticipated that the battery life willbe at least 48 hours, and the detachable end cap 24 allows for thereplacement of batteries, as required. Also, with the PCB 46 and theLEDs 48 embedded within the transparent body 42, the identifier 10 isfairly robust. A further advantage of the identifier 10 is that it isrelatively small and light, and consequently is easy to use.

1. A device for identifying a person or an object comprising: atransparent or translucent body, and embedded within the transparent ortranslucent body, a printed circuit board (PCB), a plurality of lightemitting diodes (LEDs) electrically connected to the PCB, and a diffuserfor diffusing tight emitted from the LEDs thereby to illuminate thetransparent or translucent body to form a light source for identifying aperson or an object attached to the device.
 2. A device according toclaim 1, wherein the diffuser includes a tapered portion defining asurface which is inclined relative to a longitudinal axis of the deviceat an angle of between 25° and 45°.
 3. A device according to claim 2,wherein the surface is inclined relative to the longitudinal axis of thedevice at an angle of 30°.
 4. A device according to claim 1, furthercomprising a housing defining a chamber for at least one battery.
 5. Adevice according to claim 4, wherein the diffuser forms at least part ofthe battery housing.
 6. A device according to either claim 4, whereinthe PCB is connected to the battery housing and is arranged to holdbetween three and six LEDs within the transparent or tanslucent body. 7.A device according to claim 1, wherein the LEDs and the diffuser arearranged so that, when the transparent or translucent body isilluminated, the light source is visible from all sides of the device.8. A device according to claim 1, further comprising attachment meansfor attaching the device to a person or an object.
 9. A device accordingto claim 1, further comprising a switch for controlling the flow ofcurrent through the LEDs.
 10. A device according to claim 9, wherein theswitch comprises a rotatable member which is threadably engaged with anend cap so as to be displaceable relative to the end cap between anoperative position in which it contacts a terminal on a battery and aninoperative position in which it is spaced from the terminal of thebattery.
 11. A device according to claim 10, further comprisingelastomeric O-rings forming watertight seals on the end cap and on therotatable switch member.
 12. A device according to claim 9, wherein theswitch is arranged to operate under pneumatic or hydraulic pressure. 13.A device according to claim 4, further comprising a second PCB withinthe chamber for connecting a battery contact spring to a wire extendingfrom the first PCB.
 14. A device according to claim 1, wherein thetransparent or translucent body is molded from an epoxy resin, and thePCB defines a plurality of openings for allowing the resin through thePCB during the molding of the body.
 15. A device according to claim 14,wherein the epoxy resin includes color tints.
 16. A device according toclaim 4, wherein the housing is formed from aluminum, and includes adetachable, aluminum end cap.
 17. A device according to claim 1, whereinthe transparent or translucent body includes a 19 mm diametercylindrical section, and six LEDs of 6 mm diameter are embedded withinthe cylindrical section, adjacent the diffuser, in a circularconfiguration.